Introduction

Primary choledocholithiasis is a common digestive disease that is closely related to biliary bacterial infection and host metabolic dysregulation. However, the compositions and functions of the bile microbial ecosystem and the pathogenesis of microfloral regulation of host metabolism resulting in stone formation are poorly understood.

Aims & Methods

To explore the orchestrated function of the bile microbial ecosystem and metabolite changes, biliary samples collected from patients with acute cholangitis induced by benign biliary stricture (n = 17) and primary choledocholithiasis (n = 33) were subjected to multiomics analyses. Furthermore, clinicopathological features collected over a 24-month follow-up period were examined to evaluate the predictive value of candidate microbes.

Results

Compared with that in the nonlithiasis group, bile microbiome and metabolome analyses indicated that the diversity and composition of the microbiome were reduced and the microbial and metabolic functions changed greatly in the lithiasis group. Five alpha diversity indices of the bile microbiome were significantly decreased in the lithiasis group. Furthermore, we identified 49 differential bile flora between the two groups, and the relative abundances of 6 bacteria were associated with primary choledocholithiasis relapse conditions. Multiomics analyses showed that specific changes in disease-related bacterial taxa were closely related to metabolite variation, which might reflect disease prognosis. According to pathway analyses, we revealed that bacterial infections, microbiota-derived amino acid metabolites and secondary bile acid-related pathways were significantly enriched in the stone-formation group, suggesting a novel host-microbial metabolic mechanism of primary choledocholithiasis.

Conclusion

Our study first indicates that bile host-microbial dysbiosis modulates the abnormal accumulation of metabolites might further disrupt calcium homeostasis and generate insoluble saponification. Meanwhile, bile bacterial infection inhibits the function of bile duct epithelial cells and eventually synergistically promotes stone formation. Finally, we determined the predictive value of Actinomycetes phylum reduction for recurrence in primary common bile duct stone patients.

Introduction

The success rate of endoscopic retrograde cholangiopancreatography (ERCP) is suboptimal in patients with complex surgically altered anatomy (e.g. Roux-en-Y anastomosis, pancreaticoduodenectomy) due to difficulty in advancement of scope to the target site and selective biliopancreatic duct cannulation. Although balloon-assisted enteroscopy can achieve a higher rate of intubation, its clinical application is limited by its small working channel and few compatible accessories.

Aims & Methods

We aimed to explore the feasibility and effectiveness of a novel endoscopic approach in patients with complex surgically altered anatomy.
This is a retrospective study of patients who underwent ERCP with complex surgically altered anatomy at our center with an annual ERCP volume of approximately 3000, between January 2018 and November 2022. The endoscopic procedures were performed by three senior endoscopists who had ERCP experience for at least 5 years. Long colonoscopy (measuring 168cm)-assisted ERCP was adopted as a first-line intervention, and selective biliopancreatic duct cannulation was performed after the target site (native papilla or the surgical anastomosis) was reached. For patients with failed cannulation, a plastic guide tube measuring 250 cm was inserted via the working channel of the colonoscope and its distal end was placed near the target site. The colonoscope was then withdrawn while the guide tube was left in-situ. By following the guide tube, a conventional side-viewing duodenoscope was cautiously advanced to the target site and biliopancreatic duct cannulation re-attempted.

Results

A total of 58 patients were recruited (mean age:56.7 years [standard deviation [SD]:14.4; male:36 [62.1%]]. The reconstruction methods were as follows – Roux-en-Y hepaticojejunostomy:32 (55.2%), Billroth-II gastrectomy with Braun anastomosis:11 (19.0%), pancreaticoduodenectomy:10 (17.2%) and Roux-en Y gastrectomy:5 (8.6%). Common bile duct stone was the most common indication for ERCP (n=30; 51.7%), followed by bilioenteric anastomotic stenosis (n=15; 25.9%), pancreaticojejunal anastomotic stenosis (n=7; 12.1%) and chronic pancreatitis (n=6; 10.3%). 55 (94.8%) of 58 had successful intubation by long colonoscope with a mean procedure time of 57.7minutes (SD:23.4). The mean time to reach target site was 19.1minutes (SD:9.0). The target site could not be identified in two patients and intestinal perforation occurred during endoscopic intubation in one patient. Among those with successful endoscopic intubation, biliopancreatic duct cannulation was achieved in 35 (63.6%) patients. For the remaining 20 patients with initial failure of biliopancreatic duct cannulation, intubation rate by duodenoscope was 100% by tracing the guide tube to target site. The success rate of biliopancreatic duct cannulation by duodenoscope was 85% (17/20) with a mean procedure time of 83.5 minutes (SD:21.1). The mean time to reach target site was 17.0minutes (SD:6.1). Notably, 90% (18/20) had either native papilla or pancreaticojejunostomy, in which selective biliopancreatic duct cannulation is known to be technically difficult with any type of forward-viewing scope due to unfavorable cannulation trajectory. For those with failed cannulation, two had anatomical stricture and one had impacted pancreatic stone.

Conclusion

ERCP by conventional duodenoscope with colonoscopy-assisted pre-placement of guide tube is a feasible, effective and safe alternative for patients with complex surgically altered anatomy in experienced endoscopists.

Introduction

Cholecystectomy (CCE) is commonly performed for treatment of gallstone disease. However, CCE may result in post-CCE syndrome (PCS) and diarrhea (PCD) in a subgroup of patients. In addition, epidemiological association of CCE with colorectal cancer (CRC) and metabolic-associated fatty liver disease (MAFLD) has raised concerns. CCE is expected to affect the enterohepatic circulation and result in gut microbiome changes. Such changes may account for clinical symptoms and risk for CRC and MAFLD. However, the spectrum and type of gut microbiome changes post-CCE has not been fully quantified and results have been inconsistent.

Aims & Methods

This systematic review aimed to clarify the effect of CCE on gut microbiome composition and the clinical impact. A systematic search was conducted on PubMed, Web of Science and Scopus in March 2024, combining keywords such as “cholecystectomy” or “post-cholecystectomy” with “gut microbiome” or “gut dysbiosis”. Reference and citation searches were conducted on included articles. Original articles irrespective of study design that described gut microbiome changes post-CCE were included. Articles were independently reviewed by two authors and data were extracted and synthesized using narrative review. The quality of studies was assessed using the Newcastle-Ottawa scale.

Results

A total of 1373 articles (after excluding duplicates) were initially selected, and after review of the titles and abstracts, 14 eligible studies were identified and the full text reviewed. There were 3 prospective cohort and 11 cross-sectional/ case control cohort studies, of which 13 examined the bacteria microbiome using 16S rRNA gene sequencing, and 1 cross-sectional study examined the fungal microbiome using ITS1 rDNA gene sequencing. Changes in microbiome diversity indices and relative abundances were inconsistent. Among 3 prospective cohort studies, an increase in phylum Bacteroidetes was observed in a study with post-CCE interval more than 3 months, but not in the study with 3-month post-CCE interval. One study reported no change at the phylum level, but an effect for the class Clostridia and the orders Clostridiales and Coriobacteriales within 3 days of CCE. An increase in phylum Bacteroidetes post-CCE was also seen in 3 other cross-sectional studies. Five studies attempted to correlate post-CCE microbiome changes with symptoms. A decreased Firmicutes/ Bacteroidetes (F/B) ratio was observed in patients with PCS/ PCD in 3 out of 5 studies. Although changes in relative abundances of taxa correlated with symptoms, these were inconsistent, with an increase in genus Prevotella being the only common finding in 2 out of these 5 studies. Other significant observations post-CCE included a decrease of the potentially beneficial genus Faecalibacterium and an increase in the opportunistic pathogen Escherichia/Shigella, as well as an attenuated aging-associated intestinal microbiota. The single cross-sectional study that examined post-CCE fungal microbiome changes found that the relative abundance of Candida glabrata and Aspergillus were enriched, and Candida albicans was depleted.

Conclusion

CCE is associated with significant changes in gut microbiome diversity and relative abundances of taxa. Such changes have been correlated with clinical symptoms. These microbiome changes may potentially explain the risk of CRC and MAFLD noted in epidemiological studies. Discordant results between studies may relate to differences in patient populations and study methodologies.

Introduction

Observational studies have associated cholecystectomy with cardiometabolic disorders and colorectal cancer. This is of clinical importance as the case volume of cholecystectomy has increased exponentially and cardiometabolic disorders pose a significant health burden. Understanding post-cholecystectomy gut microbiome changes may help clarify some of these observations. Published data on cholecystectomy-related gut microbiome changes are limited and mainly cross-sectional in study design, lack adequate taxonomic resolution or prediction of functional pathways as 16S rRNA sequencing rather than shotgun metagenomics sequencing was used, and observed microbiome changes have not been correlated with concomitant changes in the metabolome¹.

Aims & Methods

This exploratory prospective cohort study aimed to examine the changes in gut microbiome and systemic metabolome post-cholecystectomy. Subjects aged 21 to 65 years undergoing cholecystectomy for treatment of symptomatic gallstone disease were enrolled. Exclusion criteria included the use of antibiotics or probiotics within one month, appendicectomy, bowel surgery and inflammatory bowel disease. Biospecimens (stool, plasma and urine) were collected at baseline and one-month post-cholecystectomy. Stool microbiome was analysed by shotgun metagenomics sequencing, with assessment of 𝜔² effect size (derived from weighted Jaccard distance), α (Mann-Whitney U test for unpaired and Wilcoxon signed-rank test for paired tests) and β diversity indices (PCoA and PERMANOVA), as well as differentially abundant bacterial taxa and functional pathways (Maaslin2 R package, using false discovery rate [FDR] < 0.1). Systemic metabolome (plasma, stool and urine) was examined by targeted liquid chromatography-mass spectrometry, and Orthogonal Partial Least Squares Discriminant Analysis was performed to identify metabolites that were different post-cholecystectomy, using paired t-tests and FDR < 0.1. Correlation analysis of changes in stool microbiome and metabolome was performed.

Results

A total of 26 subjects were enrolled. The mean age was 47 years (12), with 62% (16/26) male and mean body mass index (BMI) 25.57 kg/m² (3.75). Other clinical meta-data were smoking in 15.4% (4/26), alcohol consumption in 11.5% (3/26), use of proton pump inhibitors (PPI) in 7.7% (2/26), statins usage in 23.1% (6/26), and presence of fatty liver in 15.4% (4/26). The microbiome profile of the enrolled cohort was similar to matched asymptomatic controls with intact gallbladder (with or without gallstones). One-month post-cholecystectomy, the 𝜔² effect size was 0.006 (80% power, α < 0.05). Significant differences were observed for β diversity indices after controlling for drinking status, presence of fatty liver and use of PPI. There were 32 differentially abundant bacterial taxa and 124 differentially abundant functional pathways. Analysis of observed microbiome and systemic metabolome changes revealed correlation of 9 species with plasma bile acid (chenodeoxycholic acid [CDAC]), 20 species with plasma lipids, 3 species with stool bile acids (CDCA), 9 species with stool carboxylic acids and 2 species with urinary trimethylamine N-oxide.

Conclusion

Cholecystectomy resulted in significant changes in the stool microbiome and systemic metabolome. Such changes may help explain the epidemiological association with cardiometabolic disorders. Further larger scale prospective cohort studies with longer duration of follow-up are needed to confirm these observations.

References

1. Ang TL, Koo SH, Ang D, Tan CK, Wang LM, Wong SH, Chow PKH. Postcholecystectomy Gut Microbiome Changes and the Clinical Impact: A Systematic Review With Narrative Synthesis. J Gastroenterol Hepatol. 2025 Mar;40(3):574-583.

Introduction

Cholangiocarcinoma continues to exhibit a high mortality rate despite advancements in diagnostic and therapeutic approaches. The contribution of the human microbiota to cholangiocarcinoma remains inadequately elucidated, with recent metagenomic analyses revealing a significant association between microbiota-driven carcinogenesis and cholangiocarcinoma. This investigation seeks to explore alterations in microbiota composition in relation to cholangiocarcinoma and their metabolic signatures by integrating taxonomic and functional data with metabolomic findings and in vitro experiments.

Aims & Methods

The study included patients with and without cholangiocarcinoma who underwent endoscopic retrograde cholangiopancreatography (ERCP) between February 2019 and January 2021. Bile samples were procured through endoscopic nasobiliary drainage, followed by DNA extraction, PCR amplification of the bacterial 16S rRNA gene V3-V4 region, and data analysis utilizing QIIME2. In vitro CFSE proliferation and Annexin V/PI apoptosis assays were conducted to examine the effects of metabolites on cholangiocarcinoma cells.

Results

The study encompassed a total of 24 patients. Analysis of bile fluid indicated a significantly increased abundance of Escherichia coli in the cholangiocarcinoma group. Alpha diversity analysis demonstrated a marked difference between cholangiocarcinoma and non-cholangiocarcinoma cohorts. NMR metabolic profiling identified 15 metabolites with significant concentration disparities, among which isoleucine exhibited the most pronounced variation. In vitro assays revealed that isoleucine inhibited cholangiocarcinoma cell proliferation without inducing apoptosis.

Conclusion

This study underscores the significance of biliary dysbiosis and bile metabolites, particularly isoleucine, in the development and progression of cholangiocarcinoma.

Introduction

Benign bile duct obstruction is commonly caused by choledocholithiasis, while hepato-biliary-pancreatic tumors contributed to the most of malignant obstruction. With the development of next generation sequencing technology, the existence of microbiota was confirmed in biliary system, both in healthy and illness population. The characteristics of biliary microbiota in malignant bile duct obstruction remains poorly understood.

Aims & Methods

This study aims to investigate the composition and metabolic functions of biliary microbiota in patients with malignant bile duct obstruction. The present study was designed as a case-control study, which was approved by the ethics committee of First Affiliated Hospital of Soochow University (approval number: 2020-082). Consecutive patients were prospectively enrolled from December 2022 to October 2023, including distal cholangiocarcinoma, hilar cholangiocarcinoma, pancreatic ductal adenocarcinoma, periampullary carcinoma and gallbladder carcinoma. The patients with choledocholithiasis served as controls. Bile samples were collected via endoscopic retrograde cholangiopancreatography. The inclusion criteria were as follows: (1) patients who suffered from bile duct obstruction; (2) all the diagnosis confirmed by imaging examinations or histopathological tests; (3) no antibiotics usage within the preceding three months. The exclusion criteria were as follows: (1) patients who were attacked by acute obstructive suppurative cholangitis or acute hepatic failure at the same time; (2) without gallbladder; (3) surgical history concerning upper gastrointestinal tract or common bile duct; (4) history of gastrointestinal or hepato-biliary-pancreatic neoplastic diseases. Bile samples were collected through ERCP. The microbiota was analyzed using 16S rRNA sequencing. Metabolic functions were predicted by PICRUSTs 2.0 calculation based on MetaCyc database. Bile acids were tested and identified using ultra performance liquid chromatography-tandem mass spectrometry.

Results

A total of 56 patients were successfully enrolled in this study, 25 in the tumor group and 31 in the stone group. No significant difference concerning demographics was found between the two groups. A distinct biliary microbial community was identified in patients with malignant bile duct obstruction. Firmicutes accounted for 40.67% at the phylum level in the tumor group, followed by Proteobacteria (36.44%), Bacteroidetes (11.33%), Actinobacteria (6.81%) and Fusobacteria (3.71%). The unique composition at genus level mainly consisted of Prevotella, Uruburuella, Atopostipes, Clostridium IV, Halomonas, Tannerella, Porphyromonas, Achromobacter, Rouxiella, Campylobacter, Corynebacterium, Turicibacter, Muribaculum, Selenomonas and Alloprevotella. Notably, Clostridium IV, Halomonas, Rouxiella and Turicibacter were exclusively present in the tumor group. Bile acids levels were significantly lower in the tumor group (p<0.05), except for ursodeoxycholic acid and taurocholic acid. There are 22 metabolic pathways were enriched in the tumor group.

Conclusion

This study elucidates the community and metabolic potential of biliary microbiota in malignant bile duct obstruction. The findings offer valuable insights for disease assessment and provide a foundation for further research into the role of biliary microbiota in malignancy.

References

1. Xue C, Chu Q, Zheng Q, Yuan X, Su Y, Bao Z, et al. Current understanding of the intratumoral microbiome in various tumors. Cell Rep Med 2023; 4 (1):100884.
2. Helmink BA, Khan MAW, Hermann A, Gopalakrishnan V, Wargo JA. The microbiome, cancer, and cancer therapy. Nature medicine 2019; 25 (3):377-388.
3. Li Z, Chu J, Su F, Ding X, Zhang Y, Dou L, et al. Characteristics of bile microbiota in cholelithiasis, perihilar cholangiocarcinoma, distal cholangiocarcinoma, and pancreatic cancer. Am J Transl Res 2022; 14 (5):2962-2971.

Introduction

Primary biliary cholangitis (PBC) is often associated with extrahepatic autoimmune diseases (EAIDs) such as Sjögren’s syndrome, autoimmune thyroiditis, and connective tissue disorders. While this association suggests a shared immunological predisposition, its effect on disease prognosis remains unclear.

Aims & Methods

This retrospective study included 69 patients diagnosed with PBC, excluding those with overlap syndromes involving autoimmune hepatitis. Patients were divided into two groups: isolated PBC (n = 35) and PBC associated with EAIDs (n = 34). The two groups were compared based on clinical, immunological, elastometric characteristics, disease progression, and prognostic scores (Paris I, Paris II, Rotterdam, Barcelona, Rochester, GLOBE, UK-PBC). Statistical analysis was conducted using appropriate tests, with a significance threshold set at p < 0.05.

Results

The average age at diagnosis was 55.6 years. The disease was initially suspected based on functional symptoms in 39% of cases (fatigue, pruritus, arthralgia), biological cholestasis in 33.3%, and decompensated cirrhosis in 20.3%. The most common associated autoimmune diseases were Sjögren’s syndrome (17.4%), thyroid disorders (13%), and systemic lupus erythematosus (10.1%). All patients received treatment with ursodeoxycholic acid at 13-15 mg/kg/day. No significant differences were found between the two groups regarding functional symptoms, biological markers (bilirubin, albumin, prothrombin time), autoantibodies (AMA, Anti-GP210, anti-SP100, anti-PML), non-invasive fibrosis scores (Fib4, Fibroindex, Fibroscan, S-index), or hepatic complications (HDH, cirrhosis, hepatic encephalopathy, liver-related death). Prognostic scores were also comparable between both groups: Paris I (p = 0.468), Paris II (p = 0.519), GLOBE score (p = 0.6), UK-PBC (p = 0.49), Rotterdam (p = 0.897), Barcelona (p = 0.181), Rochester (p = 0.727).

Conclusion

The presence of extrahepatic autoimmune diseases in PBC does not appear to affect the clinical, biological, or prognostic profiles of patients. Despite their frequency, these comorbidities do not seem to influence the progression of PBC.

Disclosure

None.